RandomControl release Arion for Rhinoceros v2.7.0.Beta2.
 
"Besides some other minor fixes, load of pre-v2.7.0 materials has been fixed, and the map/texture preview thumbnails works like in Af3 and Asa now. The build is available in the Customer Area."

For more info, please see: http://randomcontrol.com/blog/?p=1828